A. Range is 15°F
B. Approach is 10°F
C. Both A. & B.
D. Neither A. nor B.
Explanation:
Temperature range (T1 – T2) = 15°F
Temperature approach (T2 – tw) = 10°F
Wet-bulb temperature tw = 70°F
Related Mcqs:
- Minimum temperature upto which water can be theoretically cooled down in the cooling tower by evaporative cooling is equal to the ______________ temperature of air?
A. Wet bulb
B. Dry bulb
C. Saturation
D. Dew point - The minimum temperature to which the water can be cooled in a cooling tower is the ______________ temperature of air?
A. Ambient
B. Dry bulb
C. Dew point
D. Wet bulb - When dry bulb temperature & wet bulb temperature of moist air is the same, it means that the _________________?
A. Partial pressure of water vapour is less than the total pressure
B. Humidity is < 100% & dew point temperature of air has not reached
C. Dew point temperature of air has not reached & air is not saturated fully
D. Air is fully saturated - During sensible cooling of air, its wet bulb temperature ?
A. Decreases but dew point remains constant
B. Increases but dew point remains constant
C. Increases & the dew point decreases
D. Decreases & the dew point increases - Moist air is cooled along the line of constant ________________ , when it is passed over a cold & dry cooling coil, such that no condensation occurs ?
A. Enthalpy
B. Relative humidity
C. Wet bulb temperature
D. Dew point temperature - When the wet steam is throttled but still remains wet at the exit of the throttle valve, then its temperature & dryness fraction respectively____________________?
A. Decreases & increases
B. Increases & increases
C. Increases & decreases
D. Decreases & decreases - Heating the Hypo-eutectoid steels to 30°C above the upper critical temperature line, soaking at that temperature and then cooling slowly to the room temperature to form a pearlite & ferrite structure is called_______________________?
A. Tempering
B. Hardening
C. Annealing
D. Normalising - Evaporative cooling process employs a combination of cooling and humidification in which the____________________?
A. Sensible heat is added
B. Sensible heat is removed and the latent heat is added
C. Latent heat is removed
D. Sensible heat is added and latent heat is removed - The refractory brick which has good thermal shock resistance at high temperature but cracks on cooling below 400°C is__________________?
A. Magnesite
B. Chrome
C. Silica
D. Fireclay - The heat released by cooling one mole of copper from 400 K to room temperature (300 K) is (assume : Cp of copper is 23 J K-1mole-1) ?
A. 2300 J
B. 4600 J
C. 230 J
D. 2.3 × 106 J
